Swift开发iPhone应用：求可自定义旋转Logo的活动指示器方案（非SVProgressHUD）

一、推荐的第三方库 #

除了SVProgressHUD，这两个库完美支持自定义旋转Logo的需求：

• MBProgressHUD：这是iOS开发中非常流行的 HUD 库，灵活性极高，可以轻松替换默认指示器为你的公司Logo，并添加旋转动画。
  使用示例：

  import MBProgressHUD
  
  // 显示自定义旋转Logo
  func showCustomLogoHUD() {
      let hud = MBProgressHUD.showAdded(to: view, animated: true)
      hud.mode = .customView
      // 创建Logo图片视图
      let logoImageView = UIImageView(image: UIImage(named: "company-logo"))
      hud.customView = logoImageView
      // 添加旋转动画
      let rotationAnimation = CABasicAnimation(keyPath: "transform.rotation.z")
      rotationAnimation.toValue = NSNumber(value: Double.pi * 2)
      rotationAnimation.duration = 1.0
      rotationAnimation.isCumulative = true
      rotationAnimation.repeatCount = Float.infinity
      logoImageView.layer.add(rotationAnimation, forKey: "rotationAnimation")
      hud.label.text = "加载中..."
  }
  
  // 隐藏HUD
  func hideCustomLogoHUD() {
      MBProgressHUD.hide(for: view, animated: true)
  }
  

• PKHUD：同样是轻量且高度可定制的HUD库，支持自定义内容视图，实现Logo旋转也很简单。
  使用示例：

  import PKHUD
  
  // 显示自定义旋转Logo
  func showCustomLogoPKHUD() {
      let logoImageView = UIImageView(image: UIImage(named: "company-logo"))
      // 添加旋转动画
      let rotation = CABasicAnimation(keyPath: "transform.rotation")
      rotation.fromValue = 0
      rotation.toValue = 2 * Double.pi
      rotation.duration = 1.0
      rotation.repeatCount = .infinity
      logoImageView.layer.add(rotation, forKey: "spin")
      HUD.show(.customView(view: logoImageView))
  }
  
  // 隐藏HUD
  func hideCustomLogoPKHUD() {
      HUD.hide()
  }
  

二、纯自定义实现（无需第三方库） #

如果不想依赖第三方库，自己实现一个也很简单，下面是完整的自定义旋转指示器代码：

import UIKit

class CustomSpinnerView: UIView {
    private let logoImageView: UIImageView = {
        let imageView = UIImageView()
        imageView.image = UIImage(named: "company-logo")
        imageView.contentMode = .scaleAspectFit
        imageView.translatesAutoresizingMaskIntoConstraints = false
        return imageView
    }()
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        setupView()
    }
    
    required init?(coder: NSCoder) {
        super.init(coder: coder)
        setupView()
    }
    
    private func setupView() {
        backgroundColor = UIColor.black.withAlphaComponent(0.5)
        layer.cornerRadius = 10
        clipsToBounds = true
        
        addSubview(logoImageView)
        
        NSLayoutConstraint.activate([
            logoImageView.centerXAnchor.constraint(equalTo: centerXAnchor),
            logoImageView.centerYAnchor.constraint(equalTo: centerYAnchor),
            logoImageView.widthAnchor.constraint(equalToConstant: 60),
            logoImageView.heightAnchor.constraint(equalToConstant: 60)
        ])
    }
    
    // 开始旋转动画
    func startAnimating() {
        let rotationAnimation = CABasicAnimation(keyPath: "transform.rotation.z")
        rotationAnimation.toValue = NSNumber(value: Double.pi * 2)
        rotationAnimation.duration = 1.0
        rotationAnimation.isCumulative = true
        rotationAnimation.repeatCount = Float.infinity
        logoImageView.layer.add(rotationAnimation, forKey: "rotationAnimation")
    }
    
    // 停止旋转动画
    func stopAnimating() {
        logoImageView.layer.removeAnimation(forKey: "rotationAnimation")
    }
}

// 在ViewController中调用的示例
extension UIViewController {
    func showCustomSpinner() {
        let spinner = CustomSpinnerView(frame: view.bounds)
        spinner.tag = 999
        view.addSubview(spinner)
        spinner.startAnimating()
    }
    
    func hideCustomSpinner() {
        if let spinner = view.viewWithTag(999) as? CustomSpinnerView {
            spinner.stopAnimating()
            spinner.removeFromSuperview()
        }
    }
}

使用的时候，直接在你的ViewController里调用：

// 显示指示器
showCustomSpinner()

// 模拟异步任务后隐藏
DispatchQueue.main.asyncAfter(deadline: .now() + 3) {
    self.hideCustomSpinner()
}

这样不管是用第三方库还是自己实现，都能完美实现用公司Logo作为旋转活动指示器的需求啦！

内容的提问来源于stack exchange，提问作者Er. Vihar